code: def get_protocol(path):
      """Given a path, returns the protocol the path uses
  
      For example,
        's3://a/b/c/'  returns 's3'
        'http://a/b/c' returns 'http'
        'tmp/a/bc/'    returns ''
  
      """
      pos = path.find("://")
      if pos < 0:
          return ""
      return path[0:pos].lower()
  
file_path: turicreate/src/python/turicreate/util/_file_util.py
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import os
  import logging
  import shutil
label_desc: Use image node_id 1 for calling a global function with example usage: get_protocol(path) and returns: path, str